Web development tools enable developers to diagnose HyperText Markup Language (HTML) and Cascading Style Sheets (CSS) problems. Developers can dynamically modify Document Object Model (DOM) elements including CSS selectors and see the changes reflected immediately in the running page in a browser. To permanently apply the modifications to the markup text source document from which the page originates, however, the developer needs to locate and appropriately modify the markup text or originating JavaScript associated with the desired modification. Locating the source code text associated with the desired modification may be difficult, however, since the associated source code text might not be immediately obvious or might originate in code with which a developer is not familiar. In addition, once the source code text associated with the desired modification is located, several steps may be needed to apply the modification and actually see the results of the modification in a browser.